diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index b1498ab..19e9dfa 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -275,6 +275,7 @@
 		pag = radix_tree_delete(&mp->m_perag_tree, agno);
 		spin_unlock(&mp->m_perag_lock);
 		ASSERT(pag);
+		ASSERT(atomic_read(&pag->pag_ref) == 0);
 		call_rcu(&pag->rcu_head, __xfs_free_perag);
 	}
 }